In recent years, various structures have been provided to form a portable sheet bending brake for bending metal or plastic sheets such as are used in siding on homes and buildings. Typical patents comprise U.S. Pat. Nos. 3,161,223, 3,481,174, 3,482,427, 3,559,444, 3,817,075, 3,872,755, 4,321,817 and 4,557,132. Such brakes comprise a fixed member on which the sheet is clamped and a movable bending member for bending the sheet. A major problem with respect to such sheet bending brakes is the tendency of the bending member to move relative to the portion of the sheet being bent and thereby mar the surface of the sheet.
In U.S. Pat. No. 3,161,223, the tendency to mar the surface of the sheet material was minimized by having the intermeshing integral projections between the fixed member and the bending member, which extend longitudinally and define the hinge that connects the bending member with the fixed member having the clamping surface, positioned so that all portions of the projections do not extend above the plane of the surface of the members when the surfaces are substantially aligned. U.S. Pat. Nos. 3,481,174 and 3,482,427 were directed to an arrangement which included a floatable compensator on the bending member which engages the sheet material and, as the bending member is swung to bend the sheet, pivots so that the contact with the sheet material is maintained.
In U.S. Pat. No. 4,557,132, there is disclosed and claimed a sheet bending brake that incorporates a novel construction for minimizing the marring of the surface of the sheet material during bending; which functions without the need for added parts; which can be manufactured at low cost; which can be adapted to sheet material of various thicknesses; and which can be utilized in a novel fashion to provide a complete 180.degree. bend to the sheet material. As described in this patent, each of the fixed and movable bending members has substantially the entire length of the longitudinal edges thereof formed with longitudinally spaced intermeshing integral projections. The projections on the bending member have a plurality of aligned openings, and the projections on the fixed member have a plurality of aligned openings comprising slots extending axially with respect to the longitudinal axis of such member. A hinge pin extends through the openings of the bending member and the slots of the fixed member. The slots have a configuration such that, as the bending member is moved relative to the fixed member to bend a workpiece, the hinge pin is guided along the slots such that the contacting portion of the bending member remains substantially in the same position relative to the workpiece.
In U.S. Pat. No. 4,364,254, there is disclosed a table mounted on the sheet bending brake and extending horizontally and rearwardly from the clamping surface of the sheet bending brake. A coil stand is mounted on the end of the sheet bending brake such that the axis of the roll of sheet stock extends transversely of the longitudinal axis of the sheet bending brake so that a length of sheet material can be unrolled from the coil stand onto the table, severed from the remainder of the uncoiled stock in the coil stand and then manually transferred from the table to the sheet bending brake for bending.
Among the objectives of the present invention are to provide a combined sheet bending brake, coil support and cutter, and a method of use, which permit the leading edge of the workpiece to pass directly from the coil between the clamping member and the fixed member; which provide a portable bending brake coil support and a hand-operated cutter system that is removably mounted on the coil support; which will accurately cut the workpiece to a desired length; which require minimal modification of the portable sheet bending brake; which can be readily added to an existing portable sheet bending brake; which will provide accurate, smooth and flat edges on the workpiece; which cut the workpiece quickly and is therefore time saving; which do not damage the aluminum parts of the portable sheet bending brake; and which are low in cost; wherein the coil support has a detachable trolley member for insertion through the coil opening thereby facilitating the elevation of the coil to the bending brake; wherein the detachable trolley member with a separate base member allows the rotational dispensation of the coil stock from any flat surface; and wherein the support coil apparatus has a movable clamping track portion for allowing unobstructed passage of the coil stock material through and into the sheet bending brake to a predetermined point at which the clamping track is closed to clamp the coil such that subsequently a hand operated cutter is extendable along a track on the clamp to sever the extended end from the coil.
In accordance with the invention, a workpiece coil support is adapted for attachment to a sheet bending brake and comprises a main frame on one end of the brake. Coil trolley receiving rails support the trolley and coil and maintain the orientation of the dispensed material to the brake. A movable clamping member is attached and includes a track. The clamping member is associated with a fixed clamp surface. The coil trolley comprises opposing end supports attached by a cross-member. Situated on either side of the cross-member, and mounted on the ends of the supports, are rollers which allow the free-rotation of the coil.
In practice, the trolley is inserted through a coil so that it can be lifted with its leading edge facing toward sheet bending brake. The trolley is slid onto the receiving rails and fixed with a hitch pin. The leading edge of the coil is advanced between the fixed and movable clamping surfaces, and onto and through the opened clamping member of the sheet bending brake so that a portion of the coil rests on the fixed clamping member of the sheet bending brake to a desired length. The movable clamp of the coil support is locked to the fixed clamp holding the material therebetween. A hand-removable and hand-operable sheet cutter is then fitted to the track and extended therealong severing the material from the coil. The severed material provides a workpiece, which is then repositioned in the sheet bending brake and clamped. To prevent the coil from unwinding, a pinch roller is placed between opposing control forks mounted on the receiving rails. Spring biasing retainers are then fitted over the axles extending from the ends of the roller. The downward pull of the springs against the axles cause biasing contact between the roller and the top surface of the coil, causing a drag on the rotation of the coil.
Another embodiment of the present invention comprises a free-standing base member adapted for receiving the trolley as above described. The base comprises horizontally extending rails oppositely fixed by cross-members. Centrally extending upward from the base frame rails are support masts which terminate with receiving trolley supports. As with the main embodiment of the present invention, the trolley is inserted through the coil opening elevating, and sliding onto, the receiving supports. Control forks extend upward from the receiver supports to a point consistent with communicating with the axles of a pinch roller used to prevent the unraveling of the coil. Further, a fixed clamp bar is attached to the base rails and adapted for communication with a movable clamp bar attached to locking clamp members mounted also to the base rails. The leading edge of the coil is fed between the clamping surfaces, which are then locked. A utility hand knife is then used to score the material using the clamping bar as a guide. The material is then flexed at the score effecting the sever of the material. To prevent damage to the clamping bar, as well as the movable track of the main embodiment, due to shaving from the utility knife blade, a stainless steel strip is fitted to the edge of the clamping bar.